Ring binder mechanisms retain loose-leaf pages on rings. Ring binder mechanisms can be used in notebooks, files, briefcases, clipboards and other similar objects to give the object a loose-leaf page retaining function. A conventional ring binder mechanism has rings formed by ring members that are selectively moveable to open the rings to add and/or remove loose leaf pages and close the rings to retain loose-leaf pages on the rings. The ring members are commonly mounted on adjoining hinge plates supported by a housing for pivoting movement between open and closed positions. The undeformed housing is slightly narrower than the combined width of the hinge plates such that the housing applies a spring force that biases the ring members against movement toward the open position when they are in the closed position. If this spring force is strong, there is a risk that a user could be injured by getting a finger pinched between the ring members as the housing causes them to snap shut during closing. Thus, it is desirable to design the housing so it exerts a relatively light spring force on the ring members to reduce the risk of injury to users.
However, the absence of a strong biasing force holding the ring members in the closed position increases the risk that the rings will inadvertently open (e.g., if the ring mechanism is accidentally dropped) and fail to retain loose-leaf pages. One way to reduce the risk the rings will inadvertently open is to provide a locking system that blocks pivoting movement of the ring members from the closed position to the open position. It is desirable for the locking system to automatically lock the rings closed when the rings are moved to the closed position. It is also desirable to be able to unlock and open the rings in a single step to make the ring mechanism convenient to use.
United States Pub. App. No. 20080124166, which is commonly owned with the present application, discloses a ring mechanism having an actuator operable to engage the hinge plates and move the rings between the open and closed positions. The mechanism also includes a travel bar having a locking element connected to the actuator so the actuator can move the travel bar and locking element between a locking and unlocking position as the actuator moves the rings between the open and closed position.
The actuator in the '166 application is designed to deform during opening and closing to sequence movement of the travel bar (and its locking element) with movement of the hinge plates. During use of the actuator to open the rings, the actuator deforms to delay movement of the hinge plates from movement of the travel bar and locking element so the travel bar and locking element can be moved away from the locking position before the actuator moves the hinge plates to open the rings. During use of the actuator to close the rings, the actuator deforms to delay movement of the travel bar and locking element from movement of the hinge plates so the hinge plates can move to the closed position before the actuator moves the locking element into the locking position. This allows a user to unlock and open the rings in a single movement of the actuator. It also allows a user to close and lock the rings in a single movement of the actuator.
FIGS. 15-18 of the present application illustrate the closing action of the actuator in the '166 application. As illustrated, the travel bar 45 is connected to the actuator 15 by an intermediate connector 67 having ends 68a, 68b that are inserted into an opening in a flexible arm 38 (FIG. 15) on the actuator 15. FIG. 17 shows the configuration of the actuator 15 when the rings are open and FIG. 18 shows the configuration of the actuator during movement of the actuator to close the rings. As illustrated in FIG. 18, the flexible arm 38 deforms during closing by bending in a direction (e.g., clockwise in FIG. 18) relative to the rest of the actuator that is opposite the direction (e.g., counterclockwise in FIG. 18) in which the actuator rotates during use of the actuator to close the rings. This deformation of the flexible arm 18 delays movement of the travel bar 45 from movement of the hinge plates during closing.